The present invention relates to an ion plating apparatus using plasma and an operation method for operating such an apparatus.
Typical ion plating apparatuses are known to use a pressure gradient plasma source using arc discharge or an HCD plasma source. An ion plating apparatus comprises a plasma beam generator (plasma source). A plasma beam is generated between the plasma beam generator and a hearth (anode) placed in a vacuum chamber. The plasma beam travels into the evaporation material on the hearth to evaporate the evaporation material. Metal particles evaporated from the evaporation material are ionized and activated by the plasma beam. The ionized metal particles are deposited on a surface of a substrate placed in the vacuum chamber at a predetermined amount with being opposed to the hearth. As a result, a thin film is formed on the substrate.
In the conventional ion plating apparatus, the substrate is transferred, on completion of process, from a predetermined position to another position by means of a conveyer device. Then, another substrate is transferred to the predetermined position by the conveyer device. The ion plating apparatus continues to produce the plasma beam while exchanging the substrates. This is for a stable operation of the apparatus. More specifically, it takes a relatively long time for the plasma beam generator to produce a stable plasma beam after a down time. Accordingly, the plasma beam is continuously supplied to the hearth, evaporating the evaporation material, during the travel of the substrates. More evaporation material is evaporated when it is a sublimation material such as indium oxide doped with tin oxide (ITO). This means the evaporation material is wasted. In addition, the ionized metal particles are deposited on the inner surface or other members of the vacuum chamber. It is thus necessary to maintain the vacuum chamber more frequently to remove the depositions on the inner surface and other members of the vacuum chamber. It is particularly significant when the plasma beam generator used is a highly effective one or high-power plasma beam generator.